What is the most effective strategy to utilize the Walking Ballista Heliod combo in a competitive Magic: The Gathering deck?

The most effective strategy to use the Walking Ballista Heliod combo in a competitive Magic: The Gathering deck is to focus on generating mana quickly to play both cards early in the game. Once you have both cards on the battlefield, you can use Heliod's ability to put a counter on Walking Ballista, allowing you to deal damage to your opponent or their creatures. This combo can quickly overwhelm your opponent and lead to a swift victory.